There are various different types of speakers: Paper cones have the advantages of natural tones, low price, good rigidity, lightweight material, and high sensitivity and the disadvantages of poor moisture resistance, high level of difficulty of controlling the consistence of the manufacture, but the paper cones are very common in high-end HiFi systems, since the output of sound is uniform, and the reversibility is good.
Bulletproof fabric cone has the features of wide frequency response and low distortion, and thus it is the first choice for strong bass lovers, and its disadvantages include high cost, complicated manufacturing process, insufficient sensitivity, and poor effect of light music. Wool knit cone has the features of soft texture, and thus provides excellent performance for soft music and light music and the disadvantages of poor bass effect and lack of strength and shocking power.
Polypropylene (PP) cone is popular in high-end speakers and has the features of good consistency, low distortion, and remarkable performance in all aspects. In addition, there are fiber diaphragms and composite diaphragms, and they are expensive and thus are seldom used in common speakers.
The conventional police speaker cannot be used in police work sufficiently and is just limited to the function of providing the siren and a deterrent effect. With the limited manpower of police officers, it is necessary to use the present existing hardware resources to provide more auxiliary police functions, and the conventional police speaker still cannot provide the aforementioned function.